The one ingredient in every brand I scraped.

Here's what's funny. There's almost no other fibre that turns up like this.

Cotton's in most brands but not all. Wool turns up in maybe a third. Linen, silk, cashmere are basically luxuries — they show up in pockets.

Polyester though. 55 out of the 57 brands I scraped. Every single sportswear label, every fast-fashion catalog, every quiet-luxury knitwear brand, every workwear chain. All of them.

The only brand that came back completely polyester-free in our scrape was Pangaia. One brand. Out of fifty-seven.

And worth pausing on why — Pangaia doesn't use polyester because they literally built the entire brand on the promise of not using it. They describe themselves as a materials science company that happens to sell hoodies. The puffer jackets are stuffed with wildflowers and biopolymers instead of synthetic down.

They had to score well, or the whole brand would fall over. Intentional. Rare.

Look, for a lot of people polyester just feels like “oh I'm wearing plastic” — which, yeah, you are. But that doesn't actually explain how it got into literally every other brand. Cheapness alone doesn't do it. Luxury brands aren't cutting corners on price.

So let me tell you what makes polyester really special.

It's the universal donor of fabric. It blends with anything — cotton, wool, viscose, silk, doesn't matter, polyester plays nice with all of them. It takes any dye. It holds any shape. It survives any wash. It's basically the duct tape of textiles.

If you're a designer trying to deliver a specific drape, a specific stretch, a specific price point, polyester is in the toolbox. And it's usually the easiest answer.

So even a brand built entirely on natural fibre will still slip a bit in somewhere. The lining of the coat. The elastic in the waistband. The trim on the cuff. The thread holding two pieces of linen together.

Often it's three percent. Sometimes it's the only synthetic in an otherwise pure garment. But it's there.

Which means almost nothing you own is fully polyester-free.

If you want to see which brands lean hardest on polyester, the live polyester ranking tracks every brand we've scraped, sorted by the share of products that are 50%+ polyester.

And if you want to see the opposite end — where the cleanest natural-fibre catalogs are — we ranked them in the 10 brands with the most natural fibre. Pangaia sits at number one there, too.

For a worked example of polyester sneaking in via the trend rail, see where Zara's polyester load actually sits inside a 13,685-product catalog.